/Engine/Source/Developer/SourceControl/Public/SourceControlHelpers.h
Delegate used for performing operation on files that may need a checkout, but before they are added to source control
typedef TBaseDelegate_ThreeParams< bool, const [FString](API\Runtime\Core\Containers\FString) &, const [FText](API\Runtime\Core\Internationalization\FText) &, [FText](API\Runtime\Core\Internationalization\FText) & > FOnPostCheckOut